Predictive Value of Serum Albumin Level for the Prognosis of Severe Sepsis Without Exogenous Human Albumin Administration: A Prospective Cohort Study

Background: The prognostic significance of serum albumin levels in patients with sepsis has previously been reported; however, these studies have not excluded the potential confounding effect of exogenous albumin administration. In this study, we investigate the predictive value of serum albumin for the prognosis of severe sepsis without the interference of exogenous albumin administration. Methods: A prospective cohort study was conducted from April to November 2014 in the internal and surgical intensive care units of a tertiary care hospital. During the study period, due to a supply shortage, patients were not treated with human albumin. Serum albumin levels were measured, and laboratory and clinical data were collected at the onset of severe sepsis. Prognostic factors were analyzed using receiver operating characteristic curve and multivariate Cox proportional hazard regression analysis. Survival was assessed by Kaplan-Meier method. Results: One hundred sixteen patients were included in the study. The overall 28-day mortality was 26.7%. The most common infection sources were lower respiratory tract, abdomen/pelvis, and bloodstream. Compared to patients who survived, those who died had lower serum albumin levels and higher Acute Physiology and Chronic Health Evaluation II (APACHE II) and Sequential Organ Failure Assessment (SOFA) scores. Receiver operating characteristic curves demonstrate that albumin level is a strong predictor of 28-day mortality, and the optimal cutoff value maximizing sensitivity and specificity is 29.2 g/L. Through multivariate Cox regression analysis, low serum albumin levels (<29.2 g/L) and APACHE II scores are identified as independent risk factors for mortality. Patients with lower serum albumin levels more often had abdominal/pelvic sources of infection, acute kidney or liver injury, septic shock, and higher APACHE II and SOFA scores. The 28-day survival rate was lower for patients with serum albumin below 29.2 g/L than for patients with serum albumin at or above this level. Conclusion: Having excluded potential confounding effect of exogenous albumin administration, low serum albumin levels are associated with an increased risk of death in patients with severe sepsis.